The 35-year-old Scotland international joined the Clarets for £200,000 from Preston North End on deadline day at the end of August and has already impressed in five outings for Cotterill's side.
He told the Lancashire Evening Post: "He's a better player than what I thought I'd signed. I think he's been an excellent, calming and driving force.
"If someone rolls a ball short he's on to it like a shot because he sees it.
"He's been here five minutes and he presses a ball as well as anybody in this team because he sees it.
"He just knows it. He's a good player and others who play alongside him will benefit by copying. The best way for a player to learn is visually."
He told the Lancashire Evening Post: "He's a better player than what I thought I'd signed. I think he's been an excellent, calming and driving force.
"If someone rolls a ball short he's on to it like a shot because he sees it.
"He's been here five minutes and he presses a ball as well as anybody in this team because he sees it.
"He just knows it. He's a good player and others who play alongside him will benefit by copying. The best way for a player to learn is visually."